The department, located near Bay City, Mich., received a call that one of the soul-sucking "Harry Potter" creatures had been spotted in Smith Park and sent a lieutenant to investigate the magical happening.

An investigation determined that the "Dementor" was actually a trash bag attached to a tree, and there was no need to start practicing Patronus charms.

The lighthearted post, which has been shared about 1,000 times, explains the department's struggle to investigate the report since Dementors can't be seen by non-magical folks, also known as muggles in the popular book series by J.K. Rowling.

The department assured concerned citizens it had checked with the Ministry of Magic and all dementors had been accounted for at Azkaban — the prison where dementors work in the 'Harry Potter" world.

They also used the post as an opportunity to remind residents to help keep the city beautiful by making sure trash gets properly thrown away.